I. Field of the Invention
The present invention relates generally to screw cap removers and more particularly to such a device having adjustable and removable jaws so as to be able to lockingly engage many sizes of screw caps around substantially the entire periphery of the screw cap.
II. Description of the Prior Art
There are many types of previously-known devices for removing screw cap lids from a container. These devices are generally provided with a pair of cap engaging jaws adapted to engage diametrically opposed sides of the cap. The jaws are secured to an elongated handle so that the handle extends radially outwardly from the screw cap and thus provides leverage which enables a large torque to be exerted upon the screw cap.
U.S. Pat. Nos. 2,719,444, 2,669,142, 2,651,957, and 2,634,638 disclose such screw cap movers wherein a lever is pivotable with respect to the elongated handle of the device such that pivoting of the lever urges a slidable jaw toward a fixed jaw secured to the elongated handle in order to grip the screw cap between the jaws. One disadvantage of these previously-known devices is that when pressure is applied to the elongated handle to cause rotational movement of the screw cap, the lever is simultaneously urged toward the handle and thus the sliding jaw is subjected to excess forces which urge it into tighter contact with the screw cap lid. Such excess forces can cause deformation of the screw cap lid and even breakage of the container upon which the screw cap is secured.
The U.S. Pat. No. 2,486,523 discloses a screw cap wrench having an elongated handle and a ring member secured at one end of the handle, wherein a pivoting cam member urges a sliding jaw toward a stationary jaw. The stationary jaw includes a plurality of teeth along a portion of the inner periphery of the ring member facing the sliding jaw. Such a construction is disadvantageous in that the ring strictly limits the size of the screw cap with which the wrench can be used. Moreover, the size of the screw cap with which the wrench is operable is also limited by placement of the pivot pin of the cam member with respect to the wrench handle. In addition, as with the other previously-known screw cap wrenches, the size of the jaws is not adjustable. Thus, although some of the jaws disclosed in previously-known screw cap removers are designed so that they can grip at least a portion of the screw cap regardless of the diameter of the screw cap, the jaw exerts its force only at discrete points around the periphery of the screw cap. Consequently, the screw cap is subjected to forces which are concentrated at particular points around the periphery of the screw cap and these forces can deform the concentricity of the screw cap. Moreover, the points of concentrated stress subject the container to which the screw cap is secured to possible deformation or breakage.